Two-component Dark Matter and low scale Thermal Leptogenesis

Abstract

The observable cosmos exhibits sizable baryon asymmetry, small active neutrino masses, and the presence of dark matter (DM). To address these phenomena together, we propose a two component DM scenario in an extension of Scotogenic model, imposing $\mathbb{Z}_2 \otimes \mathbb{Z}_2^{\prime}$ symmetry. The electroweak sphaleron process converts the $\rm Y_{B-L}^{}$ yield, generated through the Leptogenesis mechanism, into the baryon asymmetry ($\rm Y_{\Delta B}^{}$) at $\rm T_{\rm sph}\sim 130$ GeV, the sphalerons decoupling temperature. In this framework, the CP asymmetry as well as the radiative neutrino mass generation explicitly involve the two DM particles, thus establishing a correlation between the baryon asymmetry, DM and observed active neutrino masses. We study in details the allowed parameter space available after considering all the constraints from the three phenomena as well as from the collider search limits, and outline the region which could potentially be tested in future DM detection experiments through direct or indirect detection searches, lepton flavor-violating decays, etc.